Below is my post on it with all kinds of pics and info.
In short, you have the fat side of a pork butt and the meat side of the pork butt.
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From the meat side, position the butt like the immediate image above. Cut a slice into the middle of the pork butt starting at the top and go to the bottom. (top of picture to bottom of picture)
Cut into the butt until the knife hits the bone then keep the whole cut about that deep. It's not a super precise cut or anything.
The whole goal is to hit the bone and have the cut where you can butterfly out the meat enough to season in there and set it on the rack somewhat butter flied.
When it is on the rack it is slightly buttered flied with seasoning all in there AND gives more surface area and the ability for the smoke to now penetrate that deep in and into the meat surrounding the split. If you didn't do this then all of that meat in there would likely get NO seasoning, bark, or smoke penetration or much flavor deep in there.
This approach solves those issues :)
Let me know if this helps :)
My full post below
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Well a few weekends ago I did 2 pork butts at 17.5 pounds total. I butterflied them so that the pork butts were more like butts hahaha. The reason I did this was to: get more seasoning on the meat for flavor get more bark because there was now more surface area get more smoke flavor and...
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